Usually restarting the bridge a few times will get it unstuck, however at 157 puppets to connect to Telegram the bridge often gets stuck at one of them, preventing the others from starting and preventing the appservice web listener from starting.

There's no consistent reason for it getting stuck, unfortunately:

• Sometimes telethon gets stuck in a reconnect loop (fix is to restart - there's no recovering from this I've found)
• Sometimes nothing happens at all - the user's telegram ID doesn't show up in the logs
• Sometimes it looks like it connected okay, but for some reason hasn't moved on. Possibly unable to get chat listing or taking too long?